Pectoralis major muscle: anatomical features of its arterial supply

Despite the extensive use of pectoralis major flaps in reconstructive surgery, certain pectoralis major musculocutaneous flaps may suffer from partial distal necrosis. The aim of the present study was to investigate the origin, length, and external diameter of its arterial pedicles to provide an anatomical basis for alternative techniques in reconstructive surgery. Thirty pectoral region specimens, pertaining to 14 fresh human adult cadavers and one stillbirth, were dissected, after retrograde injection of the brachial artery with red latex in pursuit of this aim. The thoracoacromial trunk (TAT) was the main nourishing vessel, arising from the first and the second parts of the axillary artery in 60% and 40%, respectively. The proximal segment was constantly supplied by the clavicular and the deltoid branches of the TAT, supplemented by its pectoral branch in 30% and the superior thoracic artery in 23.3%. The distal segment was constantly supplied by the lateral perforating branches of the anterior intercostal arteries and the perforating branches of the internal thoracic artery. The pectoral branch of both the TAT (P-TAT), and the axillary artery (PA) and the lateral thoracic artery participated in 90%, 66.7%, and 40%, respectively. Additionally, an arterial pedicle, from the arterial plexus inside the pectoralis minor muscle, was observed in 4/30 (13.3%). The clavicular and pectoral branches of the TAT are reliable pedicles for raising the proximal and distal segments of muscle flaps, respectively. The pectoral branch of axillary artery may be an alternative pedicle in the absence of P-TAT.